csharp_coreclr_x64 dockerfile not useful

tools/dockerfile/test/csharp_coreclr_x64/Dockerfile

@@ -1,114 +0,0 @@
-# Copyright 2015 gRPC authors.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-FROM debian:jessie
-
-# Install Git and basic packages.
-RUN apt-get update && apt-get install -y \
-  autoconf \
-  autotools-dev \
-  build-essential \
-  bzip2 \
-  ccache \
-  curl \
-  gcc \
-  gcc-multilib \
-  git \
-  golang \
-  gyp \
-  lcov \
-  libc6 \
-  libc6-dbg \
-  libc6-dev \
-  libgtest-dev \
-  libtool \
-  make \
-  perl \
-  strace \
-  python-dev \
-  python-setuptools \
-  python-yaml \
-  telnet \
-  unzip \
-  wget \
-  zip && apt-get clean
-
-#================
-# Build profiling
-RUN apt-get update && apt-get install -y time && apt-get clean
-
-#====================
-# Python dependencies
-
-# Install dependencies
-
-RUN apt-get update && apt-get install -y \
-    python-all-dev \
-    python3-all-dev \
-    python-pip
-
-# Install Python packages from PyPI
-RUN pip install pip --upgrade
-RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
-
-#================
-# C# dependencies
-
-# Update to a newer version of mono
-RUN apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 3FA7E0328081BFF6A14DA29AA6A19B38D3D831EF
-RUN echo "deb http://download.mono-project.com/repo/debian jessie main" | tee /etc/apt/sources.list.d/mono-official.list
-RUN echo "deb http://download.mono-project.com/repo/debian wheezy-apache24-compat main" | tee -a /etc/apt/sources.list.d/mono-xamarin.list
-RUN echo "deb http://download.mono-project.com/repo/debian wheezy-libjpeg62-compat main" | tee -a /etc/apt/sources.list.d/mono-xamarin.list
-
-# Install dependencies
-RUN apt-get update && apt-get -y dist-upgrade && apt-get install -y \
-    mono-devel \
-    ca-certificates-mono \
-    nuget \
-    && apt-get clean
-
-RUN nuget update -self
-
-# Install dotnet SDK based on https://www.microsoft.com/net/core#debian
-RUN apt-get update && apt-get install -y curl libunwind8 gettext
-# dotnet-dev-1.0.0-preview2-003131
-RUN curl -sSL -o dotnet100.tar.gz https://go.microsoft.com/fwlink/?LinkID=827530
-RUN mkdir -p /opt/dotnet && tar zxf dotnet100.tar.gz -C /opt/dotnet
-# dotnet-dev-1.0.1
-RUN curl -sSL -o dotnet101.tar.gz https://go.microsoft.com/fwlink/?LinkID=843453
-RUN mkdir -p /opt/dotnet && tar zxf dotnet101.tar.gz -C /opt/dotnet
-RUN ln -s /opt/dotnet/dotnet /usr/local/bin
-
-# Trigger the population of the local package cache
-ENV NUGET_XMLDOC_MODE skip
-RUN mkdir warmup \
-    && cd warmup \
-    && dotnet new \
-    && cd .. \
-    && rm -rf warmup
-
-# Prepare ccache
-RUN ln -s /usr/bin/ccache /usr/local/bin/gcc
-RUN ln -s /usr/bin/ccache /usr/local/bin/g++
-RUN ln -s /usr/bin/ccache /usr/local/bin/cc
-RUN ln -s /usr/bin/ccache /usr/local/bin/c++
-RUN ln -s /usr/bin/ccache /usr/local/bin/clang
-RUN ln -s /usr/bin/ccache /usr/local/bin/clang++
-
-
-RUN mkdir /var/local/jenkins
-
-# Define the default command.
-CMD ["bash"]

tools/run_tests/artifacts/package_targets.py

@@ -78,7 +78,7 @@ class CSharpPackage:
     if self.linux:
       return create_docker_jobspec(
           self.name,
-          'tools/dockerfile/test/csharp_coreclr_x64',
+          'tools/dockerfile/test/csharp_jessie_x64',
           'src/csharp/build_packages_dotnetcli.sh')
     else:
       return create_jobspec(self.name,